Wrong architecture.
If you have as many locations as hotels, with frequent employee replacement, there is only one great solution.
That is the classic architecture. Some call it Mainframe, other calls it Citrix/Terminal server (with no Internet access from the remote desktop), yet other calls it WebApps.
There is NO reason why huge amounts of data should exist in a hotel branch, no way it should be exportable to a USB drive in a hotel near Kremlin. They are handling GDPR personal data, even sensitive data in some cases.
The only people who should have access to bulk data are IT staff at a central location, whose access is limited with MFA - preferable good MFA (Yubikey or equivalent).
Thus wrong design causes huge data loss thru a low level employee. Nothing new here. But I think EU should fine them 4% of their global turnover since it keeps happening, they clearly are not sufficient technical or organizational means in place, despite 2 earlier warnings.